Variable-speed mechanism.



PATENTED JULY 28, 1903.

H. A. KNoX.

VARIABLE VSPEED MBGHANISM.

APPLICATION FILED FEB. 1.9. 1903.

2 SHEETS-SHEET v2.

No mmm:

' clutch members.

No. 734,591. y

` l.ATENT Patented July 28, 19013.

Friuli.

HARRY A. KNOX, OF SPRINGFIELD, MASSACHUSETTS, ASSIGNOR TO KNOX AUTOMOBILE COMPANY, OF SPRINGFIELD, MASSACHUSETTS, A CORPO- RATION.

VARIABLE-SPEED lIVI ECHANISNI.

SPECIFICATION 4forlillrlg :part Of Letters Patent No. 734,891, dated. July 28, 1903.

v `Application led February 19,1903.' Serial No. 144,046. (No model.)

To all whom it ma?) concern:

Be it known that I, HARRY A. KNOX, a citi- Vzen of the United States of America, residing at Springfield, in the county of Hampden and State of Massachusetts, have invented new and useful Improvements in Variable-Speed` rangement of the parts of the clutch mechanism and its association with the supports for the speed-changing gears in such manner that nostrains are placed on the gears proper when the clutch is in use.

The invention consists in the combination of elements, as fullydescribed, and set forth ,in the claims.

In the drawings forming part of this application, Figure lis a longitudinal section of a mechanism embodying thisinvention; and Fig. 2 is a cross-sectionalA View taken on the planes indicated by the lines l, 2, and 3,

Fig. 1. l

In carrying out this invention the drivingshaft a is made with a shoulder c thereon near one end of that part shown in Fig. 1 of the draw-A ings and with anothershoulder d thereon located not far from the opposite end. Between these shoulders all of' the gearing and clutch mechanism is mounted;` except the devices for imparting endwise motion to one of the The principalintermediate member, located between the shaft a and the sprocket-wheel b, is the member indicated by e, which, as

shown in Fig.V 1, is provided with along hub` which is fitted onto the shaftict withthe end of thehub against the shoulder c on the shaft, there being interposed between said shoulder and said hub a bearing-ringf, which maybe omitted. vThe sprocket-wheel b is provided with a hub substantially equal to the length of the hub on the member e-,over which it fits and to which it is securely keyed.

On that side of the member e. from which its hub projects are two pinions g, which rotate on studs preferably cast on e. Concentrically on the same side of the member e there is cast a double-walled fiange which is lettered h and whose sides are parallel with the axis of the shaft, the walls of this flange constituting the boundary of what is an annular recess h when looked at from the opposite side of the member e. At two opposite points the outer wall of this flange is cut away, as indicated by o', this cut being made to permit the teeth of the pinions g to enter the said annular recess h, (to engage another gear to be described,) of which the walls of the flange h form the boundaries.

The periphery of the intermediate member e is flanged on that side thereof opposite to that on which the pinions g are mounted,

`said flange extending at right .angles tothe plane of said member e. The flange is indicated by j and carries an internal rack lo, which, it will be observed by reference to Fig. l', does not extend to the full width of Ithe flange j,.a space m being left between the wall of the member e and the innerends of the teeth ofthe rack 7c, within whichspace is located a circular member n, having a long hub o, tting on and keyed to `thedrivng- 'shaft a in a fixed position, said member being located in very close proximity to that Iside of' the member e under the iiangej.

On'that side ofthe circular member n con-` tiguous to the member e there is cast a circular vflange 1o, (parallel with the axis of the shaft,) which is located in the annular recess h', on which flange gear-teeth q are cut, (see Fig. 2,) which gear-teeth mesh with the teeth `of the pinions g through the cut-away portions'il ofthe circular flange h. On a hub r,

`which rotates freely o'n the hub of the sprocket-wheel b, another circular member s `is carried, on the periphery of-whichis a Iiange t, lying at right angles to the member s, and whose inner surface is provided with gear-teeth u., which also mesh with the teeth` of the pinions g. The out-er edge of the memloer s is carried somewhat beyond the surface of the outside anges on these members to hold in place the brake-strap w, which encircles the flange f of said member. Thus IDO we have the circular member n keyed to the shaft, the circular member e loose on the shaft, and the circular member s Vrunning loosely on the hubof the member e, with pinions 'g mounted on the last-named member and engaging with teeth on the members'n and s. Therefore if the brake-strap w be tightened around the flange t of the member s the internal rack on said fiange will become stationary and the member n, rotating with the shaft ct, will cause the pinions g to travel around on said stationary rack, and thus rotate the member e andwith it the sprocketwheel b or any other transmission member, as a gear, for example, which may be secured to the member e to rotate with it. This described combination of clutch and gears thus rotates the sprocket-wheel b at one speed. To obtain another rate of speed in the opposite direction, the circular member o@ is provided, which is loosely mounted on the hub o of the member n, and on the latter is a second gear @j of a different diameter from the gear on the flange p, (see Fig. 2,) in this case of smaller diameter than said gear, and on said circular member ar the pinions z are carried on studs 2. These pinions z mesh both with the gear y on the hub o and with the gear-teeth cut on the inner surface of the fiange j of the member c. A brake-strap 3 is provided for' this member whereby it may be held against rotation, whereupon the member e will be rotated in a direction the reverse of that of the shaft a, the pinion zbeing held stationary and acting only as an intermediate between the gear y and the internal rack on the membere. The speed of rotation of the member e under these y conditions will be relative to the rotation of ,the shaft a as the diameter of the gear y is to the diameter of the member e, measured, of

` course, on the pitch-line of the several gears,

and the speed of the member e when the mem- -ber s is held against rotation will be as to the speed of the shaft as the diameter of the gear on the flangep is to the diameter of the member s, measured also on the pitch-line of the two gears. When the member s is held, the direction of the rotation of the member e is with the shaft, and when the member m is held its direction of rotation is reversed. Now to obtain a speed of the member e, and consequently of the sprocket-wheel, equal to that of the shaft and in the same direction novel means are provided herein for clutching the member c to the member n, which is fixed on the shaft by mechanism to impart an endwise sliding movement to the member 9c, whereby the member n is clamped between the members e and fr, and all of these parts therefore will rotate through said member n in'unison with the shaft without subjecting the various gears to any strain or wear.

That part of the member e between the circular flange p and the periphery of e andv contiguous to the member fn constitutes the abutment against which said member n is forced when the members@ moves endwise, as mentioned above, said member 'n having a very slight endwise motion on the shaft toward the member e. On said member a: there is a ring 4, which is secured, by means of screws 5, to the studs 2 and to two other studs 6, cast on 0c, one `of which is shown in dotted lines in'Fig. 2 and another in dotted lines on Fig. 1, this ring serving, incidentally, as a means for retaining the pinions ,e on their bearings.

rPhe means to impart endwise motion to the member :1; consists in the cam-levers 7, pivotally supported on a member 8 at 9, which is screwed onto the shaft, which is threaded at lO to receive it. The outside diameter of said member 8 is the same as the hub o, and the hub of the member has abearing on the member h, as well as on the hub 0, and on the end of the hub of the member w there is a flange l2, against which the cam-levers 7 may bear.

On that part of the shaft a lying beyond the shoulder d is a sliding collar 13, which by any suitable means maybe moved end- Wise on the shaft a to cause the free end of the cam-levers 7 to swing outwardly, said collar having pins 14 fixed therein, which have a sliding movement in holes bored in themember 8, whereby the collar 13 is made to rotate with the shaft. By moving the collar 13 to the right (see Fig. l) the free ends of the lever will move down theinclined surfaces l and effect the unclutching of the member n. No spring to retract the member fr is required, as the rotative movements of the various parts will effect their separation.

The ring 4, constituting, as it does, a retaining means for the pinions z, when the member is moved up into clutching position the pressure on said ring will bind the pinions e and prevent them from rattling during such time as the member e is being driven direct from the shaft through the clutch engagement thereof above referred to.

From the foregoing description it is clear that a novel andvery compact construction of the planetary gearing whereby one change of speed may be imparted to the transmission member b in the same direction as that of the motor is provided, and also means to obtain another rate of speed in adifferent direction to that of the motor, together with a clutch mechanism whereby the transmission member may be directly connected to the shaft frictionally, and which clutch member is entirely inclosed and protected, therefore, against the intrusion of dirt and the wear of the parts therefore greatly prolonged.

It is clear that by clamping the member n between the other two circular members which support the pinions a direct connection is established between the driving-shaft and the driven member b entirely independent of the engagement of one gear with another, and therefore all shock to the teeth of the gears in IOO IIO

weasel y the clutching operation between these parts is obviated, and in this respect this invention Vdiers from any other variable-speed mechanism within my knowledge, as all of them, so far as I am aware, make a direct connection between the driving and the driven members through all or several of the gears of the mechanism.

s While it is the better construction mechanically to provide the circular member n with a slight endwise movement, as described, the

" `degree of this movement is so slight Vthat it t 1st would be mechanically possible to spring the member n sufficiently out of line by the pressure of the member to cause itv to contact with the member e, and thus become clamped,

even,though it had no endwise movement on the driving-shaft. Sucha construction could not be as easily operated `nor would it be so desirable as that described; but it is a legitimate modication of the preferred construci tion and would clearly fall Within the scope of t the invention, and a claim is drawn thereto.

Having thus described my invention, what I claim, and desire to secure by Letters Pat* rotatable with the shaft and endwise movable thereon more or less and a gear on said member; a second circular member as e with which said driven member is positively connected, pinions mounted on said second circular member and meshing with the gear on the firstnamed circular member, a rack for said pinions and means to hold it stationary, together with means to clampvsaid first and second `circular members together.

2. Avariable-speed mechanism comprising a driving-shaft and a driven member loosely mounted thereon to transmit motion to another mechanism, a circular member as m rotatable with the shaft, gears on said circular member, supports for other gears loose ,on the shaft and located on either side of said circular member, gears on said supports coper- HARRY A. KNOX.

Witnesses:

WM. H. CHAPIN, K. I. CLEMoNs. 

